#define _CRT_SECURE_NO_WARNINGS 1
// https://www.nowcoder.com/share/jump/9466535261694664696128
/*
#include <stdio.h>
int main() {
    int row, col;
    scanf("%d %d", &row, &col);
    int matrix[row][col];
    int sum = 0;
    for (int i = 0; i < row; i++) {
        for (int j = 0; j < col; j++) {
            scanf("%d", &matrix[i][j]);
            if (matrix[i][j] > 0) {
                sum += matrix[i][j];
            }
        }
    }
    printf("%d", sum);
    return 0;
}
*/

